Related Experiment Video
Updated: Apr 21, 2026
Radionuclide-fluorescence Reporter Gene Imaging to Track Tumor Progression in Rodent Tumor Models
Published on: March 13, 2018
Experimental evaluation of radioiodinated sennoside B as a necrosis-avid tracer agent
Dongjian Zhang1, Dejian Huang, Yun Ji
1Department of Natural Medicinal Chemistry, State Key Laboratory of Natural Medicines, China Pharmaceutical University , Nanjing, Jiangsu Province , PR China .
Abstract:
Necrosis-avid agents are a class of compounds that selectively accumulate in the necrotic tissues after systemic administration, which can be used for in vivo necrosis imaging and targeted therapies. In order to search for a necrosis-avid tracer agent with improved drugability, we labelled iodine-131 on sennoside B (SB) as a naturally occurring median dianthrone compound. The necrosis targetability and clearance properties of (131)I-SB were evaluated in model rats with liver and muscle necrosis. On SPECT/CT images, a "hot spot" in the infarcted liver lobe and necrotic muscle was persistently observed at 24 h and 72 h post-injection (p.i.). Gamma counting of the tissues of interest revealed a radioactivity ratio of necrotic to viable liver at 4.6 and 3.4 and of necrotic to viable muscle at 7.0 and 8.8 at 24 h and 72 h p.i., respectively. The good match of autoradiographs and fluoromicroscopic images with corresponding histochemical staining suggested preferential uptake of (131)I-SB in necrotic tissue. Pharmacokinetic study revealed that (131)I-SB has an elimination half-life of 8.6 h. This study indicates that (131)I-SB shows not only prominent necrosis avidity but also favourable pharmacokinetics, which may serve as a potential necrosis-avid diagnostic agent for assessment of tissue viability.
Insights
Researchers developed iodine-131 labeled sennoside B ((131)I-SB) as a novel necrosis-avid agent. This compound shows high uptake in necrotic tissues, indicating its potential for diagnostic imaging and targeted therapies.
Area of Science:
- Nuclear Medicine
- Radiopharmaceutical Chemistry
- Molecular Imaging
Background:
- Necrosis-avid agents selectively target and accumulate in necrotic tissues.
- These agents are crucial for in vivo imaging and targeted therapies of necrotic areas.
- Developing novel agents with improved drugability and targeting is an ongoing research area.
Purpose of the Study:
- To synthesize and evaluate iodine-131 labeled sennoside B ((131)I-SB) as a potential necrosis-avid diagnostic agent.
- To assess the necrosis targetability and pharmacokinetic properties of (131)I-SB in vivo.
- To determine the suitability of (131)I-SB for imaging tissue viability.
Main Methods:
- Iodine-131 was labeled onto sennoside B, a naturally occurring dianthrone compound.
- SPECT/CT imaging and gamma counting were performed in rat models with induced liver and muscle necrosis.
- Autoradiography and fluoromicroscopy were used to correlate radioactivity with tissue histology.
Main Results:
- SPECT/CT images showed persistent "hot spots" in necrotic liver and muscle tissues at 24 and 72 hours post-injection.
- High radioactivity ratios of necrotic to viable tissues were observed (e.g., 7.0 for muscle at 24h).
- (131)I-SB demonstrated preferential uptake in necrotic areas, confirmed by histological correlation, with an elimination half-life of 8.6 hours.
Conclusions:
- The study successfully developed (131)I-SB, a novel agent with prominent necrosis avidity.
- Favorable pharmacokinetics and selective accumulation in necrotic tissues suggest its potential as a diagnostic agent.
- (131)I-SB may be valuable for assessing tissue viability in clinical settings.
